
/*
 * Copyright (c) 1999-2008 Mark D. Hill and David A. Wood
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met: redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer;
 * redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution;
 * neither the name of the copyright holders nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * BulkBloomFilter.cc
 *
 * Description:
 *
 *
 */

#include "mem/ruby/filters/BulkBloomFilter.hh"
#include "mem/gems_common/Map.hh"
#include "mem/ruby/common/Address.hh"

BulkBloomFilter::BulkBloomFilter(string str)
{
  string tail(str);
  string head = string_split(tail, '_');

  m_filter_size = atoi(head.c_str());
  m_filter_size_bits = log_int(m_filter_size);
  // split the filter bits in half, c0 and c1
  m_sector_bits = m_filter_size_bits - 1;

  m_temp_filter.setSize(m_filter_size);
  m_filter.setSize(m_filter_size);
  clear();

  // clear temp filter
  for(int i=0; i < m_filter_size; ++i){
    m_temp_filter[i] = 0;
  }
}

BulkBloomFilter::~BulkBloomFilter(){

}

void BulkBloomFilter::clear()
{
  for (int i = 0; i < m_filter_size; i++) {
    m_filter[i] = 0;
  }
}

void BulkBloomFilter::increment(const Address& addr)
{
  // Not used
}


void BulkBloomFilter::decrement(const Address& addr)
{
  // Not used
}

void BulkBloomFilter::merge(AbstractBloomFilter * other_filter)
{
  // TODO
}

void BulkBloomFilter::set(const Address& addr)
{
  // c0 contains the cache index bits
  int set_bits = m_sector_bits;
  int block_bits = RubySystem::getBlockSizeBits();
  int c0 = addr.bitSelect( block_bits, block_bits + set_bits - 1);
  // c1 contains the lower m_sector_bits permuted bits
  //Address permuted_bits = permute(addr);
  //int c1 = permuted_bits.bitSelect(0, set_bits-1);
  int c1 = addr.bitSelect( block_bits+set_bits, (block_bits+2*set_bits) - 1);
  //ASSERT(c0 < (m_filter_size/2));
  //ASSERT(c0 + (m_filter_size/2) < m_filter_size);
  //ASSERT(c1 < (m_filter_size/2));
  // set v0 bit
  m_filter[c0 + (m_filter_size/2)] = 1;
  // set v1 bit
  m_filter[c1] = 1;
}

void BulkBloomFilter::unset(const Address& addr)
{
  // not used
}

bool BulkBloomFilter::isSet(const Address& addr)
{
  // c0 contains the cache index bits
  int set_bits = m_sector_bits;
  int block_bits = RubySystem::getBlockSizeBits();
  int c0 = addr.bitSelect( block_bits, block_bits + set_bits - 1);
  // c1 contains the lower 10 permuted bits
  //Address permuted_bits = permute(addr);
  //int c1 = permuted_bits.bitSelect(0, set_bits-1);
  int c1 = addr.bitSelect( block_bits+set_bits, (block_bits+2*set_bits) - 1);
  //ASSERT(c0 < (m_filter_size/2));
  //ASSERT(c0 + (m_filter_size/2) < m_filter_size);
  //ASSERT(c1 < (m_filter_size/2));
  // set v0 bit
  m_temp_filter[c0 + (m_filter_size/2)] = 1;
  // set v1 bit
  m_temp_filter[c1] = 1;

  // perform filter intersection. If any c part is 0, no possibility of address being in signature.
  // get first c intersection part
  bool zero = false;
  for(int i=0; i < m_filter_size/2; ++i){
    // get intersection of signatures
    m_temp_filter[i] = m_temp_filter[i] && m_filter[i];
    zero = zero || m_temp_filter[i];
  }
  zero = !zero;
  if(zero){
    // one section is zero, no possiblility of address in signature
    // reset bits we just set
    m_temp_filter[c0 + (m_filter_size/2)] = 0;
    m_temp_filter[c1] = 0;
    return false;
  }

  // check second section
  zero = false;
  for(int i=m_filter_size/2; i < m_filter_size; ++i){
    // get intersection of signatures
    m_temp_filter[i] =  m_temp_filter[i] && m_filter[i];
    zero = zero || m_temp_filter[i];
  }
  zero = !zero;
  if(zero){
    // one section is zero, no possiblility of address in signature
    m_temp_filter[c0 + (m_filter_size/2)] = 0;
    m_temp_filter[c1] = 0;
    return false;
  }
  // one section has at least one bit set
  m_temp_filter[c0 + (m_filter_size/2)] = 0;
  m_temp_filter[c1] = 0;
  return true;
}


int BulkBloomFilter::getCount(const Address& addr)
{
  // not used
  return 0;
}

int BulkBloomFilter::getTotalCount()
{
  int count = 0;
  for (int i = 0; i < m_filter_size; i++) {
    if (m_filter[i]) {
      count++;
    }
  }
  return count;
}

int BulkBloomFilter::getIndex(const Address& addr)
{
  return get_index(addr);
}

int BulkBloomFilter::readBit(const int index) {
  return 0;
  // TODO
}

void BulkBloomFilter::writeBit(const int index, const int value) {
  // TODO
}

void BulkBloomFilter::print(ostream& out) const
{
}

int BulkBloomFilter::get_index(const Address& addr)
{
  return addr.bitSelect( RubySystem::getBlockSizeBits(), RubySystem::getBlockSizeBits() + m_filter_size_bits - 1);
}

Address BulkBloomFilter::permute(const Address & addr){
  // permutes the original address bits according to Table 5
  int block_offset = RubySystem::getBlockSizeBits();
  physical_address_t part1 = addr.bitSelect( block_offset, block_offset + 6 );
  physical_address_t part2 = addr.bitSelect( block_offset + 9, block_offset + 9 );
  physical_address_t part3 = addr.bitSelect( block_offset + 11, block_offset + 11 );
  physical_address_t part4 = addr.bitSelect( block_offset + 17, block_offset + 17 );
  physical_address_t part5 = addr.bitSelect( block_offset + 7, block_offset + 8 );
  physical_address_t part6 = addr.bitSelect( block_offset + 10, block_offset + 10 );
  physical_address_t part7 = addr.bitSelect( block_offset + 12, block_offset + 12 );
  physical_address_t part8 = addr.bitSelect( block_offset + 13, block_offset + 13 );
  physical_address_t part9 = addr.bitSelect( block_offset + 15, block_offset + 16 );
  physical_address_t part10 = addr.bitSelect( block_offset + 18, block_offset + 20 );
  physical_address_t part11 = addr.bitSelect( block_offset + 14, block_offset + 14 );

  physical_address_t result = (part1 << 14 ) | (part2 << 13 ) | (part3 << 12 ) | (part4 << 11 ) | (part5 << 9) | (part6 << 8)
    | (part7 << 7) | (part8 << 6) | (part9 << 4) | (part10 << 1) | (part11);
  // assume 32 bit addresses (both virtual and physical)
  // select the remaining high-order 11 bits
  physical_address_t remaining_bits = (addr.bitSelect( block_offset + 21, 31 )) << 21;
  result = result | remaining_bits;

  return Address(result);
}
